Scientist Unravels Mystery of Ghostly Sandy Island

Scientist Unravels Mystery of Ghostly Sandy Island
A research ship cruised through the Coral Sea, bearing down on Sandy Island. The digital scientific databases used by the researchers showed the island to be 24 kilometers (15 miles) long and about 5 kilometers (3 miles) wide. Manhattan-sized.

But when the ship reached the place where the island should have been, the researchers saw only open ocean. The water was more than a kilometer (1 mile) deep. Sandy Island simply wasn’t there. Or, it turned out, anywhere.

How in the world did this happen? It’s 2013: We have sophisticated satellite imagery and the amazing technologies of GIS. Why did elite cartographers and other specialists continue to map an island that did not actually exist?

Geographers and cartographers are learning new things every day! “It’s a really big ocean, and we certainly don’t know everything,” according to Admiral David Titley, who served as an oceanographer and navigator in the U.S. Navy.

Not enough people questioned authority. Sandy Island had been depicted on authoritative maps (off and on) since 1908. People were hesitant to question such institutions as the British or American military, Google Maps, and, yes, the National Geographic Society. (Nat Geo has been phasing out references to the island since 2000.)

Even with the most sophisticated data-collection techniques available, mapmaking still depends on knowledgeable cartographers—people who know how to read and make maps. As the article says, “[j]ust because a map looks professional, and just because a digital map may have impressive bells and whistles, doesn’t mean that the underlying data has been scrubbed of errors.” Read our Real-World Geography profile of Juan Valdes, the geographer of the National Geographic Society. In the “Geo-Connection” section, he talks about updating maps with new geographic information, such as the un-discovery of Sandy Island. According to Valdes, “NG Maps struck Sandy Island off of its database in early December 2012. Any map that we have produced of the area since then does not show the island or related bathymerty.” Can students think of other geographic changes which may cause Valdes and other cartographers to update their maps?

Most geographic changes impact political maps, which display data such as place names and borders. Valdes notes that many “place names throughout the world are reverting to their former indigenous or historical names,” such as the Canada’s Queen Charlotte Islands being re-named Haida Gwaii. Having to erase an entire landmass, such as Sandy Island, is a much more unusual occurrence! It’s not unique, however. Hurricane Sandy cut a new channel in Fire Island, New York, in 2012, for example. (Look at these USGS maps that depict the area before and after Hurricane Sandy.) Maps of Fire Island National Seashore had to be re-drawn.

Sandy Island is far from the only cartographic mystery in the ocean. Can students think of reasons why mapping the ocean is important?

The article gives the best reason: Safety. In 2005, it says, the submarine USS San Francisco was “cruising at full speed, more than 500 feet below the sea near Guam, when it slammed into an underwater mountain. Many sailors were injured, and one died later. The submarine nearly sank. Repairs cost millions of dollars.”

Access to lucrative natural resources may also inspire cartographers to map the ocean floor. Look at our map of the Arctic Seafloor. The continental shelves of many nations, including Russia, Canada, Denmark (Greenland), and Norway, converge around the Arctic Circle. Territorial claims to this area may become more controversial as technology allows greater access to the region’s oil, gas, and mineral deposits.